9-3 Doesn't like the cold!
Discussion
My OH has a 2001 9-3 SE convertible.
It normally runs fine and pulls like a train but, when it's below about 5 degrees is a real pig to start, sometimes not at all!
Once started she's OK for the rest of the day and will start fine 8 hours later.
I started off with a full service, including new plugs, a new battery, a new engine block temperature sensor, new vacuum hoses, replaced the non-return valve to the fuel tank and new fuel pressure regulator. There are no fault codes reported!
The only thing that made any difference was the first time I started the car after changing the fpr it was instant!
Is that a clue?
Any other ideas?
It normally runs fine and pulls like a train but, when it's below about 5 degrees is a real pig to start, sometimes not at all!
Once started she's OK for the rest of the day and will start fine 8 hours later.
I started off with a full service, including new plugs, a new battery, a new engine block temperature sensor, new vacuum hoses, replaced the non-return valve to the fuel tank and new fuel pressure regulator. There are no fault codes reported!
The only thing that made any difference was the first time I started the car after changing the fpr it was instant!
Is that a clue?
Any other ideas?
sounds fuel-ish to me but i'm often wrong !!
saabs do odd stuff with failing batteries but you've changed that - is the starter and it's wiring healthy?
you've changed the fpr and the non-return valve already. another consideration could be a failing pump. any leaks from the unions depressurising the system overnight? coolant temp sensor might be sending improbable values to the ecu and cold start cycle isn't being initiated (long shot but even new ones can be dodgy. very hypothetical though !)
if possible you need to check the fuel pressure at the rail before attempting to start it and also when cranking to see if it falls too low, either overnight or during start up.
paul
saabs do odd stuff with failing batteries but you've changed that - is the starter and it's wiring healthy?
you've changed the fpr and the non-return valve already. another consideration could be a failing pump. any leaks from the unions depressurising the system overnight? coolant temp sensor might be sending improbable values to the ecu and cold start cycle isn't being initiated (long shot but even new ones can be dodgy. very hypothetical though !)
if possible you need to check the fuel pressure at the rail before attempting to start it and also when cranking to see if it falls too low, either overnight or during start up.
paul
paulmakin said:
sounds fuel-ish to me but i'm often wrong !!
saabs do odd stuff with failing batteries but you've changed that - is the starter and it's wiring healthy?
you've changed the fpr and the non-return valve already. another consideration could be a failing pump. any leaks from the unions depressurising the system overnight? coolant temp sensor might be sending improbable values to the ecu and cold start cycle isn't being initiated (long shot but even new ones can be dodgy. very hypothetical though !)
if possible you need to check the fuel pressure at the rail before attempting to start it and also when cranking to see if it falls too low, either overnight or during start up.
paul
I'm sort of looking at fuel pressure, although I did check the other morning and when releasing the valve plenty of fuel squirted out. I'm just looking on Amazon for a fuel pressure gauge!saabs do odd stuff with failing batteries but you've changed that - is the starter and it's wiring healthy?
you've changed the fpr and the non-return valve already. another consideration could be a failing pump. any leaks from the unions depressurising the system overnight? coolant temp sensor might be sending improbable values to the ecu and cold start cycle isn't being initiated (long shot but even new ones can be dodgy. very hypothetical though !)
if possible you need to check the fuel pressure at the rail before attempting to start it and also when cranking to see if it falls too low, either overnight or during start up.
paul
A strange one this morning to throw into the mix... I went out to try abd start the car. Turned over well but showed absolutely no sign of firing.
Purely on a hunch, and for no other reason, I went to loosen the fuel cap to see if there was any pressure build up, or vacuum. Loosened it gently but there was no tell-tale hiss from the tank.
Got into the car, turned the key and she started instantly!
So maybe the fuel pump/pressure is the number one suspect?
I'll give it a try again tomorrow morning!
Purely on a hunch, and for no other reason, I went to loosen the fuel cap to see if there was any pressure build up, or vacuum. Loosened it gently but there was no tell-tale hiss from the tank.
Got into the car, turned the key and she started instantly!
So maybe the fuel pump/pressure is the number one suspect?
I'll give it a try again tomorrow morning!
just thought - is the spark known good ?
in olden times some electrical connections/joints could be affected by cold - things contracted and lost good contact. i also had something that had got water in the connector block which then froze and pushed the join apart - probably an alfa, it was usually an alfa playing up !
paul
in olden times some electrical connections/joints could be affected by cold - things contracted and lost good contact. i also had something that had got water in the connector block which then froze and pushed the join apart - probably an alfa, it was usually an alfa playing up !
paul
Another confusing update today...
It’s got cold again so was really reluctant to start. SWMBO got in to try starting it and I pinched the vacuum pipe to the fuel pressure closed. The car started instantly!?
Now, bearing in mind I’ve just changed the fpr, any suggestions as to what this can be? Are there any check valves or non return valves in this part of the vacuum circuit which could have failed?
Getting to the end of my tether now, even my TVRs are less problematical!
It’s got cold again so was really reluctant to start. SWMBO got in to try starting it and I pinched the vacuum pipe to the fuel pressure closed. The car started instantly!?
Now, bearing in mind I’ve just changed the fpr, any suggestions as to what this can be? Are there any check valves or non return valves in this part of the vacuum circuit which could have failed?
Getting to the end of my tether now, even my TVRs are less problematical!
Sorry this is a few months off, but I sorted this by swapping my Evap purge valve. I also had hard starts after filling the tank and the car would usually crank for 5 seconds before turning over.
You've probably already sorted this, but popping this here in case anyone else has the same issue.
You've probably already sorted this, but popping this here in case anyone else has the same issue.
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